cad software

Hi Everyone--
I am teaching a computer aided drawing/architectural drawing class and am
interested in appropriate software for our Macs and high school students,
grades 9 through 12. Right now, all we have is the draw and paint programs
in Claris works and we need to upgrade. Is there anyone out there with
expertise in this area who might share it? Thanks in advance!
Kathy Fiske
Needham High School
Needham, MA